1. Field of the Invention
The present invention relates to a stage apparatus, a lithography apparatus, and an article manufacturing method.
2. Description of the Related Art
A stage apparatus, which has a movable portion and a fixed portion, moves with a workpiece mounted thereon. In order to supply utility to a unit located on the side of the movable portion, the movable portion and the fixed portion are connected by wires and pipes. The wires and pipes between the movable portion and the fixed portion are made of flexible material and thus can bend and deform according to the movement of the stage. The bending and deforming of the wires and/or pipes during the movement of the stage apparatus can cause particles (also referred to as dust).
In general, in order to prevent the diffusion of particles, a dust generating source is covered with a cover. Japanese Patent Laid-Open No. 2008-004918 discloses a method that includes covering a bundle of wires and pipes with a surrounding member having a bellows structure or the like with an excellent flexibility, and evacuating the inside of the surrounding member.
Covering the wires and pipes with a flexible cover, however, do not lead to the fundamental solution because the cover itself generates dust due to its bending and deforming.
There is also a method that includes arranging a hard cover that does not deform for covering the whole movable range of wires and pipes on the side of the fixed portion of a stage, thereby preventing the diffusion of particles generated from the wires and pipes to the surrounding environment without generating particles from the cover itself. This arrangement, however, requires a slit opening having a length of a stage stroke and a width of the thickness of the wires and pipes on a side of the cover in order to take out the wires and/or pipes connected to the side of the movable portion, resulting in a remarkably deteriorated sealing property of the cover.